Paint Touchups

Hi Again (2nd post today)

Just finished getting a bit of paint tuition, no matter how careful I have been it was inevitable that I would get scratches and chips on the new paint work, so I lured Mick around with a Ltr of Morgans spiced rum and had a good tuition session.

The main damage was on the back of the headlight which could be removed to work on but the more difficult area was on the side of the wing which the steel bezel of my watch chipped.

The headlight was scratched when I used the riveter on the back and also a bit of heat from drilling the holes lifted the clear coat.

I first started with 320 dry and feathered the scratches out.

Then I used 800 wet to remove the 320 scratches and the rest got a scuffing with a scotch pad as the whole shell would be painted.

I dried off and then a light coat of primer.

This was then rubbed down with 800 wet and re- primed as necessary.

A small amount of paint was mixed 50, 50 with thinners.

After tac ragging a very light coat was sprayed on, this was then blown with air from the gun until the solvent had evaporated.

Then many coats of base was applied, air drying between coats until there was a good covering, once happy with the coverage Mick advised that for metallics it is best when finished to lightly, from a distance mist on a final coat to bring out the depth of the metallic. (I assume)

Next was the clear coat.

The clearcoat is a 2 pak system where hardener is added 50 50 but and a big but it will not dry in a garage without a little assistance. In the paint shop infrared lights are used and this assists in the hardening and it takes approx 1 hr. Mick say's that without this assistance it would still be too soft to flat down for at least 36 hrs so an accelerator is mixed with the hardener.

The first coat is important and is called the glue coat, this is misted on very lightly and is left for 5 mins to settle and slightly go off.

You can see the droplets from the misting and also the fumes so a mask is important to use.

Once the five minutes is up then you can give it a wet coat and leave it to dry.

This is left overnight and tomorrow I shall give it a light flattening down with 1500 wet then using my polishing machine lightly polish keeping the polish head moving continuously at low speed to prevent heat build up and burning.

The chip on the side was a slightly different approach, this was due to the paint having to blend into the surrounding paint so as you can't see that it has been repaired, and to achieve this there are a few little tricks Mick showed me.

The rubbing down is the same 320 grit and feather in, then, 800 wet and a wet scotch pad to remove any 320 scratches, and carry on a good 300mm or so with the 800 from the repair for blending.

You then need to mask all around the area and lightly spray with primer.

Again the primer is rubbed back with 800 wet ensuring that all of the edges are feathered in and no straight edges from the masking tape.

Once feather in the area can be cleaned of dust and tack ragged. new masking was prepared for the edge, this is masking where the edge has been folded over so only half of the masking is sticky. This is then stuck to the edge with the folded section slightly overlapping the edge. The idea being that the spray pressure from the gun will slightly lift the loose edge allowing the spray to lightly get under so as there is no solid masking edges.

Once masked you can then start lighting applying coats, it is important for the blending of the sides to start spraying from the sides and not towards the side, so start at one end and spray to the centre then from the other end towards the centre. 

Again after the final coat lightly mist on from a distance. The paint dries relatively quickly as after each coat you blow dry it.

Next for the clear coat, again you follow the same procedure, a glue coat first and allow to dry for 5 minutes followed by the final coat, also working from the outside in. This time because it is loosely masked on the edges you will get an interface line, the trick for removing this is to replace the clear coat in the spray gun with thinners and to lightly spray the interface edges. While you spray you look with the light until you see the edge disappear.

I shall leave this overnight to dry and then flat down with 1500 wet and use the polishing machine on it with finishing compound.

I learnt a lot today but unfortunately the stone chip in the top of the wing could not be handled in the same way as it would require most of the wing to be resprayed, so it was just touched with a spot of paint and then when dry a spot of clear coat applied, this will get polished out along with the rest tomorrow.

Simple

see ya Paul